1. Field
This disclosure relates generally to the field of wireless communications and more specifically to the devices and methods for wireless system acquisition.
2. Background
Wireless communication systems, also known as radio access networks (RANs), provide mobile device users with wireless access to packet-switched networks, such as the Internet, and various communication services and content, such as voice, data, multimedia, Web browsing and other. These wireless communication systems may be multiple-access systems capable of supporting communication with multiple mobile devices by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include time division multiple access (TDMA) systems, such as global system for mobile communications (GSM), code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, Universal Mobile Telecommunications Systems (UMTS) including WCDMA, HSPA, HSUPA, 3GPP Long Term Evolution (LTE) systems and others.
GSM is currently one of the most popular communication systems in the world. GSM radio access networks operate in a number of different frequency bands. For example, second-generation (2G) GSM RANs operate in the 900 MHz or 1800 MHz bands. Third-generation (3G) GSM RANs, including Enhanced Data rates for GSM Evolution (EDGE) systems, operate in 850 MHz and 1900 MHz bands. Many other wireless communication systems, such as cdma2000, WCDMA, EV-DO, and WiMAX, are deployed in the same frequency spectrum as the GSM networks and often cause interference in operation of the GSM networks. For example, if other networks are deployed in same band, it is possible that the power of these networks would be higher than the power of the GSM network. In such a case, a mobile device trying to acquire GSM service will analyze signals from other systems first before finding GSM signals, thereby increasing an amount of time used to find GSM service. Therefore, there is a need to improve GSM system acquisition procedures in presence of collocated wireless communication systems operating in the same spectrum.